JP2008284340A - Motor and oct endoscope probe with the motor - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a motor or a geared motor for mounting on a probe by which inflexible parts on the tip end of an OCT endoscope probe can be shortened and effective optical transmission to a subject is enabled. <P>SOLUTION: In a housing, a rotor with a shaft is rotatably placed on the center of a magnet and a field coil is placed facing the magnet via a gap on a housing inner wall to form the DC brushless motor. The outer diameter of the motor is selected not higher than 3 mm. The end part of the shaft is cut out obliquely against the axial direction of the shaft to form the obliquely formed face of the shaft as an optical reflection face. For the geared motor, the outer diameter of a gear head is also selected not higher than 3 mm and the end part of the output shaft of the gear head instead of the shaft is cut out obliquely against the axial direction of the output shaft to form the obliquely formed face as the optical reflection face. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a motor used for an OCT type endoscope probe and an OCT endoscope probe using the motor.

  In recent years, the use of images in medical care has become widespread, and the importance of noninvasive and non-contact measurement of internal information of a subject has been increasing.

  Conventionally, non-invasive and non-contact measurement of information inside a subject such as a living body has been mainly performed by X-rays. However, the use of X-rays has caused radiation exposure problems and imaging of biological functions. There is a problem of difficulty, and observation of tissue in a body cavity by an ultrasonic endoscope has been performed.

  However, the ultrasonic endoscope has not so high spatial resolution and cannot know information such as physiological composition other than morphology. Further, when the ultrasonic endoscope is used, a medium such as water is required, so that there is a problem that the treatment for the observation of the subject is complicated.

For this reason, recently, OCT (Optical Coherence) is used to visualize the information inside the subject using light.
Various techniques related to (Tomography) have been proposed. For example, Patent Document 1 discloses the prior art. In this method, an OCT endoscope probe is inserted into a body cavity organ, and then an OCT scan is performed to obtain a tomographic image of the organ vessel wall.

US2005 / 0143664

In order to reliably perform scanning of light necessary for tomographic image observation with a simple operation, in Patent Document 1 shown in FIG. 13, an OCT endoscope probe 100 in which a small-diameter motor 101 is arranged at a probe tip 102 is provided. Is formed. Furthermore, a prism or mirror is fixed as a scanner 105 that reflects the emitted light from the optical fiber 103 by 45 degrees at the end of the shaft 104 of the motor 101 facing the optical fiber 103 (FIG. 13 shows an example of the prism). Shown). In Patent Document 1, the light emitted from the optical fiber 103 is reflected by 45 degrees on the surface of the scanner 105, and the shaft 104 is rotated to change the optical path to an angle of 90 degrees with respect to the optical axis direction of the optical fiber 103. Thus, the OCT scan inside the subject is performed.

  In order to reduce pain to the patient as a subject, the outer diameter dimension of the OCT endoscope probe needs to be made as small as possible, and at the same time, the OCT endoscope probe is used to scan a desired site. It is desirable to be able to bend to a portion close to the tip. However, in the case of the OCT endoscope probe 100 disclosed in Patent Document 1, since the scanner 105 is mounted on the probe tip 102, there are the following problems.

  First, a portion that cannot be bent is generated in the probe tip portion 102 by the space occupied by the scanner 105 in the internal space of the probe tip portion 102, and the portion that cannot be bent becomes long. .

  Secondly, since both the motor 101 and the scanner 105 have small dimensions, it is difficult to increase the mounting accuracy of the shaft 104 of the motor 101 and the scanner 105, and the optical path of the light after reflection by the scanner 105 as the mounting accuracy decreases. Is not as desired, and efficient light transmission to the subject is not possible.

  Thirdly, since it is necessary to rotate the shaft 104 together with the scanner 105, the small-diameter motor 101 requires excessive torque when the shaft 104 rotates. In order to output this torque, the diameter of the motor 101 must be increased. As a result, the diameter of the OCT endoscope probe 100 is increased.

Fourth, since it is necessary to separately prepare an optical component to be the scanner 105, the number of components increases.

The motor according to claim 1 of the present invention includes a magnet, a field coil, a housing and a shaft,
Furthermore, the end of the shaft is formed obliquely with respect to the axial direction of the shaft,
The motor is characterized in that the oblique formation surface of the shaft is formed on a light reflection surface.

The geared motor according to claim 2 includes a motor and a gear head for reduction,
The motor includes a magnet, a field coil, a housing, and a shaft,
A pinion is formed at the end of the shaft, and the gear head is drivingly connected to the motor via the pinion.
Furthermore, the end of the output shaft of the gear head is formed obliquely with respect to the axial direction of the output shaft,
The geared motor is characterized in that the oblique formation surface of the output shaft is formed on a light reflection surface.

  The motor or geared motor according to claim 3, wherein the reflecting surface is formed by forming a reflecting film on the oblique forming surface. It is a motor.

  The motor or geared motor according to claim 4 is characterized in that the reflecting surface is formed by mirror-polishing the oblique forming surface. is there.

  Further, in the motor or the geared motor according to claim 5, a light reflection surface is formed on the oblique formation surface by mirror-polishing the oblique formation surface and further forming a reflective film on the oblique formation surface. The motor or the geared motor according to claim 1 or 2.

Further, in the motor or the geared motor according to claim 6, the oblique formation surface is made of a vitreous base alloy,
3. The motor or geared motor according to claim 1, wherein a surface roughness Ry of the oblique formation surface is set to 0.4 μm or less.

Further, in the motor or the geared motor according to claim 7, the oblique formation surface is made of a vitreous base alloy,
A surface roughness Ry of the oblique formation surface is set to 0.4 μm or less, and a light reflection surface is formed on the oblique formation surface by forming a reflective film on the oblique formation surface. The motor or the geared motor according to claim 1 or 2.

In the motor according to claim 8, the entire shaft is made of a vitreous base alloy,
4. The motor according to claim 1, wherein a surface roughness Ry of the reflection surface or the oblique formation surface is set to 0.4 μm or less.

Further, in the geared motor according to claim 9, the entire output shaft is made of a vitreous base alloy,
4. The geared motor according to claim 2, wherein a surface roughness Ry of the reflection surface or the oblique formation surface is set to 0.4 μm or less. 5.

Furthermore, the OCT endoscope probe according to claim 10 includes an optical fiber, and the motor or the geared motor according to any one of claims 1 to 9,
The motor or the geared motor is arranged at the end portion of the OCT endoscope probe body,
The reflecting surface faces the end of the optical fiber;
The OCT endoscope probe is characterized in that light emitted from an end of the optical fiber is reflected by the reflecting surface and its optical path is converted.

The OCT endoscope probe according to claim 11 includes an optical fiber, and the motor or the geared motor according to any one of claims 1 to 9,
The motor or the geared motor is arranged at the end portion of the OCT endoscope probe body,
A graded index optical fiber or GRIN lens is provided at the end of the optical fiber,
The reflective surface is opposed to an end of the graded index optical fiber or GRIN lens,
An OCT endoscope probe characterized in that light propagating through the optical fiber and emitted from the end of the graded index optical fiber or GRIN lens is reflected by the reflecting surface and its optical path is converted. It is.

Furthermore, in the OCT endoscope probe according to claim 12, the length of the graded index optical fiber is:
The OCT endoscope probe according to claim 11, wherein the probe is set to one-fourth of the meandering period of light propagating in the core of the graded index optical fiber, or an odd multiple of one-fourth. It is.

The OCT endoscope probe according to claim 13, wherein the length of the graded index optical fiber is:
A quarter of the meandering period of light propagating in the core of the graded index optical fiber.
The OCT endoscope probe according to claim 11, wherein the OCT endoscope probe is set to a half of the first to second.

  The OCT endoscope probe according to claim 14 is characterized in that the length of the GRIN lens is set to 0.25P (where P is the pitch of the GRIN lens) or an odd multiple of the 0.25P. The OCT endoscope probe according to claim 11.

  The OCT endoscope probe according to claim 15 is characterized in that the length of the GRIN lens is set between 0.25P and 0.5P (where P is the pitch of the GRIN lens). Item 12. The OCT endoscope probe according to Item 11.

  According to the present invention, since the end portion of the motor shaft or the output shaft end portion of the geared motor is formed as a light reflecting surface, there is no need for a scanner optical component such as a mirror or a prism as in the prior art. Therefore, the space occupied by the scanner in the internal space of the probe tip can be eliminated, and the unbendable portion of the OCT endoscope probe tip can be shortened. Furthermore, the number of parts can be reduced.

  Furthermore, since the light reflection surface is formed directly at the shaft end or the output shaft end, the light path of the light reflected by the reflection surface can be made as desired, and efficient light transmission to the subject can be achieved. It becomes possible.

  Furthermore, since no other parts such as the optical components for the scanner can be attached to the shaft or the output shaft, it is possible to rotate the shaft or the output shaft with a small torque, thereby suppressing the increase in size of the motor or the geared motor. I can do it. Therefore, it is possible to suppress an increase in the diameter of the entire OCT endoscope probe.

  Further, by removing the optical component for the scanner, it is possible to reduce one axis deviation element between the core shaft of the optical fiber and the shaft of the motor or the geared motor.

  Further, according to the motor or the geared motor according to claim 3 or 4, the shaft end portion or the output shaft is formed by forming a reflection film on the shaft end portion or the output shaft end portion or performing mirror polishing. Since the light reflection efficiency at the end portion is improved, the light propagation efficiency is also improved.

According to the motor or the geared motor according to claim 6, 8, or 9, the entire shaft or the output shaft, or at least the reflecting surface of the end of the shaft or the output shaft is made of a vitreous base alloy. Thus, it is possible to improve the surface smoothness of the reflecting surface by taking advantage of the properties of the vitreous base alloy having no crystal grain boundaries. Therefore, the vitreous base alloy has excellent surface smoothness due to its excellent mold transfer during injection molding and polishing during polishing, and as a result, the reflection efficiency on the manufactured reflecting surface is improved, and the light Propagation efficiency is also improved.

Further, according to the motor or the geared motor according to claim 5, the reflective film is formed after forming the oblique formation surface as a base on which the reflective film is formed into a mirror surface. As a result, the reflection efficiency on the reflection surface can be further improved.

  Further, by providing a graded index optical fiber or a GRIN lens at the end of the optical fiber, it is possible to configure an OCT endoscope probe capable of OCT scanning by collimating or converging the light emitted from the optical fiber. . Therefore, as in the present invention, even if the light reflection surface at the time of OCT scanning is reduced due to the unnecessary use of the optical components for the scanner, the light can be efficiently propagated to the reflection surface. It is possible to suppress a decrease in propagation efficiency.

<First Embodiment>
Hereinafter, embodiments of a motor and an OCT endoscope probe according to the present invention will be described in detail with reference to FIGS. FIG. 1 is a cross-sectional view of the motor according to the first embodiment, and FIG. 2 is an exploded perspective view showing a stator structure of the motor of FIG. 5 is a side view of the motor of FIG. 1, FIG. 6 is a partially enlarged view of the shaft end of the motor of FIG. 1, and FIG. 7 is an internal structure of the OCT endoscope probe on which the motor of FIG. It is a schematic diagram.

  As shown in FIG. 1, the motor 1 includes a magnet 2, a field coil 3, a housing 4 and a shaft 5. 2, the stator of the motor 1 includes a housing 4, a field coil 3, a lead wire guide 6, an end flange 7, and a flexible substrate 8.

  The outer appearance of the housing 4 has a substantially cylindrical shape, and is provided with notches 24 and 24 at one end. The field coil 3 includes a total of three tap wires 9 and a twisted wire 12 serving as a neutral point. The lead wire guide 6 includes four groove portions 10. The end flange 7 is provided with a bearing 11 (see FIG. 1).

On the other hand, as shown in FIG. 1, the field coil 3 is arranged and fixed on the inner wall of the housing 4, and the lead wire guide 6 is arranged on the tap line 9 side of the field coil 3. Further, a rotor composed of a magnet 2 and a shaft 5 passing through the center of the magnet 2 is inserted so as to face the inside of the field coil 3 through a gap, and is rotatably held by bearings 11 and 11. To do. In this way, the magnet 2 and the shaft 5 are disposed in the housing 4.

  The tap wire 9 and the twisted wire 12 drawn from the field coil 3 are connected to the flexible substrates 8 and 8 along the groove portion 10 of the lead wire guide 6. With the configuration as described above, the DC brushless motor 1 is formed, and the outer diameter L (see FIG. 5) of the entire motor 1 can be selected to be about 2 mm which is 3 mm or less.

At this time, by directly connecting the feeding land 13 of the flexible substrates 8 and 8 with the tap wire 9 and the twisted wire 12 by soldering, and fixing the groove 10 with an adhesive or the like, the tap wire is directly connected. 9. Overloading is not applied to the twisted wire 12 and each connection point, and the structure prevents the disconnection, and the fixing strength is also increased.

  The flexible substrates 8 and 8 are bent and accommodated along the cutout portions 24 and 24, so that the flexible substrates 8 and 8 are drawn out of the motor 1 without protruding from the outer diameter of the motor 1.

Further, in the motor 1 according to the present invention, the end portion of the shaft 5 is cut obliquely with respect to the axial direction of the shaft 5 as shown in FIGS. It is formed obliquely with respect to the axial direction. The cutting angle θ may be set to a desired angle depending on the required characteristics of the OCT endoscope probe on which the motor 1 is mounted. In this embodiment, the case of 45 degrees is shown as an example. The shaft 5 is usually made of stainless steel.

  A reflection film 14 is formed on the oblique formation surface 5a of the shaft 5 (see FIG. 6 (a)) or mirror-polished (see FIG. 6 (b)) to form a light reflection surface. Is done. When mirror polishing is performed, mirror finishing is performed by mechanically polishing the oblique formation surface 5a. When the reflective film 14 is formed, a highly reflective metal film such as aluminum, nickel, gold, or silver, or a dielectric multilayer film is formed on the surface of the oblique formation surface 5a. As the film forming method, vapor deposition, sputtering, CVD, plating, coating, or the like may be applied.

Alternatively, the entire shaft 5 may be composed of a vitreous base alloy, or at least only the slant forming surface 5a is composed of a vitreous base alloy, and the slant forming surface 5a made of this vitreous base alloy is formed at the end of the shaft 5. You may join to a part. In any case, the reflective surface or the oblique formation surface 5a is made of a vitreous base alloy, but the surface roughness Ry of the reflection surface or the oblique formation surface 5a should be set to 0.4 μm or less, more preferably 0.1 μm or less. And By keeping the surface roughness Ry within the above range, it is possible to prevent the light reflection efficiency from decreasing on the reflecting surface.

As the vitreous base alloy, it is particularly preferable to use a vitreous base alloy having a composition mainly composed of one or more elements such as Fe, Ni, Cu, Ti, and Zr.

In the case where the slant forming surface 5a or the entire shaft 5 is made of a vitreous base alloy, the slant forming surface 5a or the entire shaft 5 is manufactured by injection molding. In particular, it is possible to polish the mold for forming the oblique formation surface 5a to be a reflecting surface and set the mold surface roughness Ry to 0.4 μm or less, more preferably 0.1 μm or less after the transfer as described above. This is desirable from the viewpoint of preventing the light reflection efficiency from being lowered on the reflecting surface.

Alternatively, by combining the above technical elements, for example, the oblique formation surface 5a of the shaft 5 is mirror-polished, and further the reflective film 14 is formed on the oblique formation surface 5a, thereby forming a light reflection surface on the oblique formation surface 5a. You may do it. Alternatively, the entire shaft 5 is made of a vitreous base alloy, and the surface roughness Ry of the oblique formation surface 5a of the shaft 5 is set to 0.4 μm or less, and the reflection film 14 is further formed on the oblique formation surface 5a. By forming a film, a light reflection surface may be formed on the oblique formation surface 5a. Alternatively, only the oblique formation surface 5a is made of a vitreous base alloy, the surface roughness Ry of the oblique formation surface 5a is set to 0.4 μm or less, and the reflective film 14 is further formed on the oblique formation surface 5a. By forming a film, a light reflection surface may be formed on the oblique formation surface 5a.

The motor 1 configured as described above is mounted on the OCT endoscope probe 15 shown in FIG.
A single mode optical fiber 16 is provided in the OCT endoscope probe 15 as a light propagation path, and a motor 1 is disposed at the end of the OCT endoscope probe 15 main body so that the reflecting surface is an optical fiber. Opposed to 16 ends. Light emitted from a light source (not shown) propagates through the core of the optical fiber 16, and the light is emitted from the end of the optical fiber 16. The emitted light is reflected by the reflecting surface, and its optical path is converted by 90 degrees to form an image by irradiating the organ. Furthermore, a tomographic image of the organ canal wall is obtained by rotating the reflecting surface by driving the motor 1 and performing OCT scanning.

A graded index optical fiber 17 is provided at the end of the optical fiber 16 in order to focus the light by collimating the light emitted from the optical fiber 16 or converging the light. The reflection surface is disposed opposite to the end of the graded index optical fiber 17, so that the light propagated through the optical fiber 16 and emitted from the end of the graded index optical fiber 17 is reflected by the reflection surface. Then, the optical path is converted by 90 degrees, and the organ is irradiated to obtain a tomographic image of the organ tube wall.

  The graded index optical fiber 17 includes a clad and a core whose refractive index distribution exhibits a parabolic gradient. Further, the length Lg, when applied for the collimation, is set to a length corresponding to one-fourth of the meandering period of light propagating in the core or an odd multiple thereof. On the other hand, when it is used for light convergence, it is set between ¼ and ½ of the meander cycle of light propagating in the core.

  When the graded index optical fiber 17 is provided, the graded index optical fiber 17 may be fused and connected to one end of the optical fiber 16, and then the graded index optical fiber 17 may be cut at a desired core length Lg.

  The graded index optical fiber 17 may be replaced with a GRIN lens. When the GRIN lens is used for collimation, the length of the GRIN lens (corresponding to the Lg) may be set to 0.25P (where P is the pitch of the GRIN lens) or an odd multiple of 0.25P. On the other hand, when used for light convergence, the length of the GRIN lens (corresponding to the Lg) may be set between 0.25P and 0.5P.

  In this embodiment, the optical component for a scanner (prism 105 in FIG. 13) existing in the conventional OCT endoscope probe 100 is removed, and the end surface of the shaft 5 is used as a light reflection surface during OCT scanning. Accordingly, as the optical components for the scanner are not required, the light reflection surface during OCT scanning becomes smaller. However, by providing the graded index optical fiber 17 (or GRIN lens), the spread of light propagating to the end surface of the shaft 5 can be suppressed and light can be efficiently propagated to the reflecting surface. It is possible to suppress a decrease in propagation efficiency.

  As described above, according to the present embodiment, since the end portion of the shaft 5 of the motor 1 is formed as a light reflecting surface, optical components for a scanner such as a mirror or a prism are not required as in the prior art. Therefore, the space occupied by the scanner in the internal space of the probe tip can be eliminated, and the non-bendable portion of the tip of the OCT endoscope probe 15 can be shortened. Furthermore, the number of parts can be reduced.

  Furthermore, since the light reflecting surface is formed directly at the end of the shaft 5, the light path of the light after reflection on the reflecting surface can be made as desired, and efficient light transmission to the subject is possible. .

  Further, since another component such as the optical component for the scanner cannot be attached to the shaft 5 of the motor 1, the shaft 5 can be rotated with a small torque, and the enlargement of the motor 1 can be suppressed. Therefore, it is possible to suppress an increase in the diameter of the entire OCT endoscope probe 15.

  Further, by removing the optical component for the scanner, it is possible to reduce the axis deviation element between the core shaft of the optical fiber 16 and the shaft of the motor 1 by one.

  Further, by forming the reflection film 14 at the end portion of the shaft 5 or performing mirror polishing, the light reflection efficiency at the end portion of the shaft 5 is improved, so that the light propagation efficiency is also improved.

Further, since there is no crystal grain boundary in the vitreous base alloy, the surface smoothness of the reflecting surface is improved by forming the entire shaft 5 or at least the reflecting surface of the end of the shaft 5 with the vitreous base alloy. It becomes possible to make it. Therefore, the vitreous base alloy has excellent surface smoothness due to its excellent mold transfer during injection molding and polishing during polishing. As a result, the reflection efficiency on the manufactured reflecting surface is improved, and Propagation efficiency is also improved.

Further, the oblique formation surface 5a of the shaft 5 is mirror-polished, and a reflection film 14 is formed on the oblique formation surface 5a to form a light reflection surface on the oblique formation surface 5a, or the entire shaft 5 is made of glass. An obliquely formed surface is formed by forming the reflective film 14 on the obliquely formed surface 5a after the surface roughness Ry of the obliquely formed surface 5a of the shaft 5 is set to 0.4 μm or less. The light reflecting surface is formed on 5a, or only the oblique formation surface 5a is made of a vitreous base alloy, and the surface roughness Ry of the oblique formation surface 5a is set to 0.4 μm or less. By forming the reflective film 14 on the oblique formation surface 5a, forming the light reflection surface on the oblique formation surface 5a, the mirror formation of the oblique formation surface 5a serving as a base on which the reflection film 14 is formed is formed. Then, the reflective film 14 can be formed. Thereby, it becomes possible to further improve the reflection efficiency on the reflection surface.

  The present embodiment can be variously changed based on the technical idea. For example, the configuration of the motor 1 may be changed to a configuration having a motor outer diameter of about 1.5 mm as shown in FIGS. . FIG. 3 is a cross-sectional view of a motor 18 according to a modification of the first embodiment, and FIG. 4 is an exploded perspective view showing a stator structure of the motor 18 of FIG. In addition, regarding the description of the motor 18, the same number is attached | subjected to the location which overlaps with the motor 1, and the overlapping description is abbreviate | omitted or simplified and described. The stator of the motor 18 includes a housing 19, a field coil 3, a lead wire guide 20, an end flange 21, and flexible substrates 22 and 23.

  The appearance of the housing 19 has a substantially cylindrical shape, and is provided with notches 24 and 24 at one end. The field coil 3 includes a tap wire 9. The lead wire guide 20 includes a step portion 25 and three groove portions 10. The end flange 21 has a shape that also serves as a bearing, and is provided with flat portions 26 and 27 on the outer peripheral surface. Further, the flexible substrates 22 and 23 are arranged and fixed to the flat portions 26 and 27, respectively, with the same configuration.

  As shown in FIG. 3, the field coil 3 is arranged and fixed on the inner wall of the housing 19, and the lead wire guide 20 is arranged on the tap line 9 side of the field coil 3. Further, a rotor composed of a magnet 2 and a shaft 5 penetrating the center thereof is inserted into the field coil 3 through a gap, and also serves as a bearing fitted and fixed to each end of the housing 19. The flange 28 and the end flange 21 are rotatably held. Further, the tap wire 9 is routed around the gap provided by the groove portion 10 and the step portion 25 of the lead wire guide 20 to form a total of three tap wires one by one and a twisted wire serving as a neutral point. By connecting the tap wire and the twisted wire to the flexible boards 22 and 23 by soldering, the lead wire of the field coil 3 can be connected to the outer peripheral surface of the motor 18.

  At this time, the groove portion 10 and the step portion 25 are filled with an adhesive or the like, and the power supply lands 29 of the flexible boards 22 and 23 are connected to the tap wire and the twisted wire by soldering. By adhering to each other, the direct tap wire and each connection point are not overloaded, and a structure that prevents disconnection is obtained, and the fixing strength is also increased.

  The motors 1 and 18 of the present embodiment have the above-described power feeding unit structure, and the end of the shaft 5 on which the reflection surface is formed protrudes toward the drawer side of the flexible substrates 8, 22, and 23. When the motors 1 and 18 are mounted in the OCT endoscope probe 15, it is not necessary to bend the flexible substrates 8, 22, and 23 when the flexible substrate is routed in the probe 15. Therefore, disconnection of the flexible substrates 8, 22, and 23 can be prevented, and the occurrence of R (corner R) at the bent portion that occurs with bending can be eliminated. Therefore, it is possible to suppress an increase in the diameter of the probe 15 and shorten a portion where the tip of the probe 15 cannot be bent.

<Second Embodiment>
Next, embodiments of the geared motor and the OCT endoscope probe according to the present invention will be described in detail with reference to FIGS. FIG. 8 is a cross-sectional view of the geared motor according to the second embodiment, and FIG. 9 is a cross-sectional view taken along the line AA in FIG. 10 is a perspective view of the shaft showing the pinion formed at the end of the shaft of the motor, FIG. 11 is a partially enlarged view of the end of the output shaft of the gear head, and FIG. 12 is an OCT equipped with the geared motor of FIG. It is a schematic diagram of an endoscopic probe internal structure. In addition, the same number is attached | subjected to the same location as 1st Embodiment, and the overlapping description is abbreviate | omitted or simplified and demonstrated.

  As shown in FIG. 8, the geared motor 30 includes a motor 1 and a gear head 31. In the figure, 1 is a motor, and 31 is a reduction gear head that is drivingly connected to the motor 1 via a pinion 32 formed on the shaft 5. In the present embodiment, the structure of the motor 1 may be the structure shown in FIG. 1 or 3 (in FIG. 8, the motor 1 of FIG. 1 is shown as an example).

  8 and 10, a pinion 32 having an outer diameter equal to or smaller than the outer diameter of the shaft 5 is integrally formed at the end of the shaft 5. Normally, the pinion 32 is formed by subjecting the shaft 5 itself to cutting processing such as hobbing or rolling, but other methods, for example, a member on which the pinion is formed is joined to the tip of the motor shaft. Thus, the pinion 32 can be formed by an appropriate method.

  When the pinion 32 is formed by cutting or rolling the shaft 5 itself, after adjusting the outer diameter dimensional accuracy and surface roughness by centerlessly processing the shaft 5 member made of a round bar such as stainless steel. The pinion 32 is formed at the end by cutting or rolling, and then the shaft 5 provided with the pinion 32 is finished through processes such as heat treatment and barrel polishing. Note that the pinion 32 is not necessarily formed at the most distal end of the shaft 5.

  In the present embodiment, the outer diameter of the pinion 32 is set to be equal to or smaller than the outer diameter of the shaft 5 in order to obtain a large reduction ratio by reducing the diameter of the pinion. The lower limit of the outer diameter of the pinion 32 is not particularly limited, but it is generally preferable that the outer diameter of the shaft 5 is at least about 80% from the viewpoint of strength.

  The reduction gear head 31 includes a housing 33, a reduction gear mechanism 34 to which the pinion 32 is drivingly connected, an output shaft 35 that is disposed on the output side (tip side) and is rotatably supported by the bearing 11. The pinion 32 meshes with the first gear of the reduction gear mechanism 34. The structure of the speed reduction gear mechanism 34 included in the speed reduction gear head 31 is arbitrary, and various mechanisms can be applied. In this embodiment, the speed reduction gear mechanism section 34 is constituted by a planetary gear speed reduction mechanism. The basic structure of this planetary gear speed reduction mechanism is composed of two sets of independent carrier units 36a and 36b arranged in order from the motor 1 side to the output shaft 35 side, and one set provided at the base end portion of the output shaft 35. Carrier unit 36c.

  Each of the carrier units 36a and 36b has three shaft portions 37 for supporting the planetary gears on the surface on the motor 1 side so as to protrude in the circumferential direction so as to be equally divided by 120 °, and on the surface on the counter motor 1 side. A plate-like carrier 39 having a sun gear 38 projecting from the center thereof, and a planetary gear 40 rotatably supported by each shaft portion 37 (planetary gear 40 having an arrangement relationship of 120 ° in the circumferential direction) And. Further, the carrier unit 36c has three shaft portions 37c for supporting the planetary gear on the surface on the motor 1 side so as to protrude in the circumferential direction so as to be equal to 120 °, and the center of the surface on the counter motor 1 side. A plate-like carrier 39c having an output shaft 35 fixed to the base end portion (or formed integrally with the base end portion) and a planetary gear 40c rotatably supported by each shaft portion 37c. Yes. An internal gear 41 is provided on the inner surface of the housing 33 in which the reduction gear mechanism 34 is disposed.

  As described above, the planetary gears 40 and 40c of the carrier units 36a to 36c mesh with the internal gear 41, and between adjacent carrier units, the sun gear 38 of the carrier unit on the motor 1 side is connected to each of the carrier units on the non-motor 1 side. The three planetary gears 40 and 40c mesh with each other, and the three planetary gears 40 of the first stage carrier unit 36a mesh with the pinion 32 formed on the motor shaft 5. Thereby, the rotation of the pinion 32 is transmitted to the output shaft 35 via the three carrier units 36a to 36c. The outer diameter of the gear head 31 configured as described above is selected to be about 1.5 to 2 mm. Therefore, the outer diameter Lgm (see FIG. 8) of the entire geared motor 30 can be set to about 1.5 to 2 mm which is 3 mm or less.

Furthermore, the geared motor 30 according to the present embodiment is configured so that the end of the output shaft 35 is cut obliquely with respect to the axial direction of the output shaft 35 as shown in FIGS. Is formed obliquely with respect to the axial direction of the output shaft 35. The cutting angle φ may be set to a desired angle depending on the required characteristics of the OCT endoscope probe on which the geared motor 30 is mounted. In this embodiment, the case of 45 degrees is shown as an example.

  Whether the reflection film 14 is formed on the oblique formation surface 35a of the output shaft 35 (see FIG. 11A) or mirror-polished (see FIG. 11B), the light reflection surface is formed. It is formed. When mirror polishing is performed, mirror finishing is performed by mechanically polishing the oblique formation surface 35a. When the reflective film 14 is formed, a highly reflective metal film such as aluminum, nickel, gold, or silver, or a dielectric multilayer film is formed on the oblique forming surface 35a. As the film forming method, vapor deposition, sputtering, CVD, plating, coating, or the like may be applied.

Alternatively, the entire output shaft 35 may be made of a vitreous base alloy, or at least only the oblique forming surface 35a is made of a vitreous base alloy, and the oblique forming surface 35a made of this vitreous base alloy is used as the output shaft 35. You may join to the edge part. In any case, the reflection surface or the oblique formation surface 35a is made of a vitreous base alloy, but the surface roughness Ry of the reflection surface or the oblique formation surface 35a is set to 0.4 μm or less, more preferably 0.1 μm or less. I will do it. By keeping the surface roughness Ry within the above range, it is possible to prevent the light reflection efficiency from decreasing on the reflecting surface.

As the vitreous base alloy, it is particularly preferable to use a vitreous base alloy having a composition mainly composed of one or more elements such as Fe, Ni, Cu, Ti, and Zr.

In the case where the oblique forming surface 35a or the entire output shaft 35 is made of a glassy base alloy, the oblique forming surface 35a or the entire output shaft 35 is manufactured by injection molding. In particular, it is possible to polish the mold for forming the slant forming surface 35a to be a reflecting surface and set the mold surface roughness Ry to 0.4 μm or less, more preferably 0.1 μm or less after the transfer as described above. This is desirable from the viewpoint of preventing the light reflection efficiency from being lowered on the reflecting surface.

Alternatively, by combining the above technical elements, for example, the oblique formation surface 35a of the output shaft 35 is mirror-polished, and further the reflective film 14 is formed on the oblique formation surface 35a, thereby providing a light reflection surface on the oblique formation surface 35a. It may be formed. Alternatively, the entire output shaft 35 is made of a vitreous base alloy, and the surface roughness Ry of the oblique formation surface 35a of the output shaft 35 is set to 0.4 μm or less, and the reflection film 14 is further formed on the oblique formation surface 35a. A light reflecting surface may be formed on the oblique forming surface 35a by forming a film on the surface. Alternatively, only the oblique formation surface 35a is made of a vitreous base alloy, the surface roughness Ry of the oblique formation surface 35a is set to 0.4 μm or less, and the reflective film 14 is further formed on the oblique formation surface 35a. By forming a film, a light reflection surface may be formed on the oblique formation surface 35a.

The geared motor 30 configured as described above is mounted on the OCT endoscope probe 15 shown in FIG. Since the geared motor 30 is disposed at the end portion of the OCT endoscope probe 15 main body, the reflecting surface is disposed opposite to the end of the graded index optical fiber 17 (or GRIN lens) provided in the optical fiber 16. Is done. Light emitted from a light source (not shown) propagates through the core of the optical fiber 16, and the light is emitted from the end of the optical fiber 16. The emitted light is reflected by the reflecting surface, and its optical path is converted by 90 degrees to form an image by irradiating the organ. Furthermore, the tomographic image of the organ vessel wall is obtained by rotating the reflecting surface by driving the motor 1 and performing OCT scanning.

  As described above, according to the present embodiment, since the end portion of the output shaft 35 of the geared motor 30 is formed as a light reflecting surface, an optical component for a scanner such as a mirror or a prism as in the prior art becomes unnecessary. Accordingly, it is possible to eliminate the space occupied by the scanner in the internal space of the probe distal end portion, and it is possible to shorten the unbendable portion of the distal end portion of the OCT endoscope probe 15. Furthermore, the number of parts can be reduced.

  Furthermore, since the light reflecting surface is directly formed at the end of the output shaft 35, the optical path of the light after being reflected by the reflecting surface can be made as desired, and efficient light transmission to the subject can be performed.

  Further, since another component such as the optical component for the scanner cannot be attached to the output shaft 35, the output shaft 35 can be rotated with a small torque, and the enlargement of the geared motor 30 can be suppressed. Therefore, it is possible to suppress an increase in the diameter of the entire OCT endoscope probe 15.

  Further, by forming the reflective film 14 at the end of the output shaft 35 or by performing mirror polishing, the light reflection efficiency at the end of the output shaft 35 is improved, so that the light propagation efficiency is also improved.

  Further, by removing the optical component for the scanner, it is possible to reduce the axis deviation element between the core shaft of the optical fiber 16 and the shaft of the geared motor 30 by one.

  In this embodiment, the optical component for scanner (prism 105 in FIG. 13) existing in the conventional OCT endoscope probe 100 is removed, and the end surface of the output shaft 35 is used as a light reflection surface during OCT scanning. Accordingly, as the optical components for the scanner are not required, the light reflection surface during OCT scanning becomes smaller. However, by providing the graded index optical fiber 17 (or GRIN lens), it is possible to efficiently propagate the light to the reflecting surface while suppressing the spread of the light propagating to the end face of the output shaft 35. It is possible to suppress a decrease in propagation efficiency.

Further, since there is no crystal grain boundary in the vitreous base alloy, the surface smoothness of the reflecting surface can be obtained by forming the entire output shaft 35 or at least the reflecting surface of the end of the output shaft 35 with the vitreous base alloy. Can be improved. Therefore, the vitreous base alloy has excellent surface smoothness due to its excellent mold transfer during injection molding and polishing during polishing. As a result, the reflection efficiency on the manufactured reflecting surface is improved, and Propagation efficiency is also improved.

Further, the oblique formation surface 35a of the output shaft 35 is mirror-polished, and further the reflective film 14 is formed on the oblique formation surface 35a to form a light reflection surface on the oblique formation surface 35a, or the entire output shaft 35 By configuring the surface roughness Ry of the oblique formation surface 35a of the output shaft 35 to 0.4 μm or less, which is made of a vitreous base alloy, and further forming the reflective film 14 on the oblique formation surface 35a, A light reflecting surface is formed on the oblique forming surface 35a, or only the oblique forming surface 35a is made of a vitreous base alloy, and the surface roughness Ry of the oblique forming surface 35a is set to 0.4 μm or less. Further, by forming the reflective film 14 on the oblique formation surface 35a, and forming the light reflection surface on the oblique formation surface 35a, the oblique formation surface 35a serving as a base on which the reflection film 14 is formed is formed. The reflective film 14 can be formed after the mirror surface is formed. Thereby, it becomes possible to further improve the reflection efficiency on the reflection surface.

  The geared motor 30 according to the present embodiment forms the flexible substrate storage grooves 42 and 42 in the housing 33, stores the flexible substrates 8 and 8 in the flexible substrate storage grooves 42 and 42, and further has a reflective surface. Because the end of the output shaft 35 protrudes toward the flexible substrate 8, 8, the flexible substrate 8, 8 is mounted in the probe 15 when the geared motor 30 is mounted in the OCT endoscope probe 15. It is not necessary to bend the flexible substrates 8 and 8 when routing. Therefore, disconnection of the flexible substrates 8 and 8 can be prevented, and the occurrence of R (corner R) in the bent portion that occurs with bending can be eliminated. Therefore, it is possible to suppress an increase in the diameter of the probe 15 and shorten a portion where the tip of the probe 15 cannot be bent.

  The motor and the geared motor of the present invention are applicable to an endoscope probe in the medical field, particularly an endoscope probe used as an OCT type.

1 is a cross-sectional view of a motor according to a first embodiment of the present invention. The disassembled perspective view which shows the stator structure of the motor of FIG. Sectional drawing of the motor which concerns on the example of a change of 1st Embodiment. The disassembled perspective view which shows the stator structure of the motor of FIG. The side view of the motor of FIG. (a) It is the elements on larger scale of the shaft edge part of the motor of FIG. 1, and is the elements on larger scale showing the shaft edge part which formed the reflecting film in the diagonal formation surface. (b) It is the elements on larger scale of the shaft edge part of the motor of FIG. 1, and is the elements on larger scale showing the shaft edge part which mirror-polished the diagonal formation surface. The schematic diagram of the internal structure of the OCT endoscope probe which mounts the motor of FIG. Sectional drawing of the geared motor which concerns on 2nd Embodiment. Sectional drawing in alignment with the AA in FIG. The shaft perspective view which shows the pinion formed in the motor shaft end part of FIG. (a) It is the elements on larger scale of the output-shaft end part of the geared motor of FIG. 8, and is the elements on larger scale showing the output-shaft end part which formed the reflecting film in the diagonal formation surface. (b) It is the elements on larger scale of the output-shaft edge part of the geared motor of FIG. 8, and is the elements on larger scale showing the output-shaft edge part which mirror-finished the diagonal formation surface. FIG. 9 is a schematic diagram of the internal structure of an OCT endoscope probe on which the geared motor of FIG. 8 is mounted. Schematic diagram of the internal structure of a conventional OCT endoscope probe equipped with a motor.

Explanation of symbols

1, 18 Motor 2 Magnet 3 Field coil 4, 19 (Motor) housing 5 Shaft 6, 20 Lead wire guide 7, 21 End flange 8, 22, 23 Flexible substrate 9 Tap wire
10 Groove
11 Bearing
12 Line
13, 29 Power feeding land
14 Reflective film
15 OCT endoscope probe
16 single-mode optical fiber
17 Graded index optical fiber
24 Notch
25 steps
26, 27 Plane section
28 Flange
30 geared motor
31 Gear head
32 pinion
33 (Gearhead) Housing
34 Gear mechanism for reduction
35 Output shaft
36a, 36b, 36c Carrier unit
37, 37c Shaft
38 sun gear
39, 39c career
40, 40c planetary gear
41 Internal gear
42 Flexible substrate storage groove

Claims (15)

The motor includes a magnet, a field coil, a housing and a shaft,
Furthermore, the end of the shaft is formed obliquely with respect to the axial direction of the shaft,
The motor according to claim 1, wherein an oblique formation surface of the shaft is formed on a light reflection surface. The geared motor includes a motor and a gear head for reduction,
The motor includes a magnet, a field coil, a housing, and a shaft,
A pinion is formed at the end of the shaft, and the gear head is drivingly connected to the motor via the pinion.
Furthermore, the end of the output shaft of the gear head is formed obliquely with respect to the axial direction of the output shaft,
A geared motor, wherein the output shaft has a slanting surface formed on a light reflecting surface.   The motor or geared motor according to claim 1, wherein the reflective surface is formed by forming a reflective film on the oblique formation surface.   The motor or geared motor according to claim 1 or 2, wherein the reflecting surface is formed by mirror-polishing the oblique forming surface.   3. The light reflecting surface is formed on the oblique forming surface by mirror-polishing the oblique forming surface and further forming a reflective film on the oblique forming surface. Motor or geared motor. The oblique forming surface is made of a vitreous base alloy,
3. The motor or geared motor according to claim 1, wherein a surface roughness Ry of the oblique formation surface is set to 0.4 μm or less. The oblique forming surface is made of a vitreous base alloy,
A surface roughness Ry of the oblique formation surface is set to 0.4 μm or less, and a light reflection surface is formed on the oblique formation surface by forming a reflective film on the oblique formation surface. The motor or geared motor according to claim 1 or 2. The entire shaft is made of a vitreous base alloy,
4. The motor according to claim 1, wherein a surface roughness Ry of the reflection surface or the oblique formation surface is set to 0.4 μm or less. The entire output shaft is made of a vitreous base alloy,
4. The geared motor according to claim 2, wherein a surface roughness Ry of the reflection surface or the oblique formation surface is set to 0.4 μm or less. An OCT endoscope probe includes an optical fiber, and the motor or the geared motor according to any one of claims 1 to 9,
The motor or the geared motor is arranged at the end portion of the OCT endoscope probe body,
The reflecting surface faces the end of the optical fiber;
An OCT endoscope probe characterized in that light emitted from an end of the optical fiber is reflected by the reflecting surface and its optical path is converted. An OCT endoscope probe includes an optical fiber, and the motor or the geared motor according to any one of claims 1 to 9,
The motor or the geared motor is arranged at the end portion of the OCT endoscope probe body,
A graded index optical fiber or GRIN lens is provided at the end of the optical fiber,
The reflective surface is opposed to an end of the graded index optical fiber or GRIN lens,
An OCT endoscope probe characterized in that light propagating through the optical fiber and emitted from the end of the graded index optical fiber or GRIN lens is reflected by the reflecting surface and its optical path is converted. . The length of the graded index optical fiber is:
The OCT endoscope probe according to claim 11, wherein the probe is set to one-fourth of the meandering period of light propagating in the core of the graded index optical fiber, or an odd multiple of one-fourth. . The length of the graded index optical fiber is:
A quarter of the meandering period of light propagating in the core of the graded index optical fiber.
The OCT endoscope probe according to claim 11, wherein the OCT endoscope probe is set to a half of. The OCT endoscope probe according to claim 11, wherein the length of the GRIN lens is set to 0.25P (where P is the pitch of the GRIN lens) or an odd multiple of the 0.25P. 12. The OCT endoscope probe according to claim 11, wherein the length of the GRIN lens is set between 0.25P and 0.5P (where P is the pitch of the GRIN lens).

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